SoundEar 3 Advanced Noise Warning Sign

SoundEar 3

Current Loop 4-20mA Output

The SoundEar 3 Noise Warning Sign includes standard 4-20mA Current Loop outputs. These provide a signal that does not degrade due to resistance, allowing for longer cable runs, limited by the ability to drive the current.

Selectable dB measurement range
Select Fast/Slow, Max or Leq for output
Periodic Leq output option

Two Outputs

There are two current loop outputs on the SoundEar 3, so you can select two different parameters to monitor. Both outputs are set to the same measurement range, but you can select different parameters, as described below.

Output Parameters

Each current loop output can be one of the following noise measurement parameters:

LAFmax (maximum Fast sound level)
LASmax (maximum Slow sound level)
LAeq,1s (average sound level every second)
LCpeak ('C' weighted Peak)
LAeq,15 (average sound level over 15 minutes)
LAeq,30 (average sound level over 30 minutes)
LAeq,60 (average sound level over 60 minutes)

Current Loop Output Settings

Measurement Range

The overall measurement range of the SoundEar 3 is 30dB to 120dB. You can process this whole range over the current loop output, or you can select the range of interest.

In the example above, the first output is the average sound level every second (probably the most useful parameter available) while the second output is the average over a 15 minute period. A sound level of 50dB will be the minimum (4mA) and a sound level of 90dB will be the maximum (20mA).

Power Requirements

The SoundEar 3 comes with two powering options: USB (5V) or 24VDC. When using the current loop output the unit must be powered by 24VDC, it will not work with the USB option. For convenience, the 24VDC power connections are on the same connector as the current loop outputs and ground.

Connecting Up

At the rear of the noise warning sign there is a connector block - the green part on the image. This connector pulls out of its socket and contains screw terminals to connect the following: